MP3 Player ATmega168+STA013/
Another mp3 player. The firmware supports display connection from Nokia3510 (b/w). What else: volume +/-, go to next/previous track, go to 10 tracks, go to folders (if you have a display). If you do not want to, the display can not be soldered, three LEDs are enough: red, white, green. I did not solder the display, I have enough LEDs as indicators of operating modes. The author has a soldered display, I also have a display, but with a display from Nokia3510, the player in the case will look bulky. Therefore, I will not solder the display yet.
A few words about the design: it works with an 8GB (SDHC) card, which means it will work with 32GB as well. All constant resistances and capacitances (not electrolytes) are 0603 in size. The downside is that it does not play files with a variable bitrate (I personally have almost no such files, or rather, he plays them, but during the bitrate change the sound disappears for a moment), everything is basically, 256kbps and 320kbps. The screen displays the volume level, track name (8.3), battery capacity.